Trump slams handling of Brexit by British PM Theresa May

U.S. President Donald Trump meets with Ireland's Prime Minister (Taoiseach) Leo Varadkar in the Oval Office of the White House in Washington, U.S., March 14, 2018.

Before Mr Varadkar's arrival, Mr Trump tweeted that he looked forward to making a trade deal with the United Kingdom, several hours before British MPs in the House of Commons were due to vote on whether they should seek an extension for Brexit from the EU.

"I'm surprised at how badly it's all gone from the standpoint of a negotiation", he said.

"I'd like to see that whole situation with Brexit work out", Trump added. "I don't think another vote would be possible because it would be very unfair to the people who won, who say, 'What do you mean you're going to take another vote?' That will be tough".

Mr Trump also used Mr Varadkar's visit to the White House yesterday to warn Ireland and the EU the United States is "going to tariff a lot of their products coming in because the European Union treats us very, very unfairly".

The prime minister said while their views on Brexit differ, the relationship between the USA and Ireland remains strong.

Sitting beside Mr Varadkar, Mr Trump claimed the process of trying to reach a trade deal between the USA and the European Union contained difficulties.

"She's got to do what she's got to do but I think it could have been negotiated in a different manner, frankly".

Ahead of that make or break moment, United States president Trump gave his take on how well things are going.

Brexit won't spoil the relationship, even given Trump's history of turning on leaders who cross him, said Marquette University historian Timothy G. McMahon, president of the American Conference for Irish Studies. Mr Trump said the "issue on the Border of Ireland is one of the most complex points". "I regret Brexit's happening".

Ireland is at the center of the practical discussion of how Britain would separate itself from the European Union and its open movement of goods and people, because the only affected land border runs between Ireland and Northern Ireland.

"I thought it would happen, it did happen, and both sides are very, very cemented in". I believe in free trade.

"We shouldn't have a hard border or anything to obstruct the peace process".